The research on life science and material science has brought higher requirements of three-dimensional microscopic imaging. In the related art, three-dimensional microscopic imaging technologies with a wide-field microscope are used for photosensitive fluorescence samples or biological samples. However there are problems: not only fluorescence signals of the sample on a focal plane of an objective lens are excited by the exciting light, but also fluorescence signals of the sample on planes out of the focus of the objective lens are excited by the exciting light, so that a light intensity of each pixel of an imaging sensor is a superposition of a fluorescence light intensity on the focal plane, a fluorescence light intensity on the planes out of focus and noise, and a resolution of the image on each depth may be lower. This three-dimensional microscopic imaging needs to scan the whole sample layer-by-layer to obtain a set of image sequences at different depths, and then noise is eliminated via computational methods and a three-dimensional structure of the sample is obtained through fuzzy reconstruction.